This invention relates to a collapsible steering column assembly.
A collapsible steering column assembly is known from EP-A-0 705194 that includes means to absorb energy transmitted by the steering column upon collapse, the means including a generally U-shaped wire clip with arms embracing two pins, which are spaced-apart and between which a skid member, slidably housed within a mounting bracket, is guided and can pass to draw the clip over the pins to deform it.
Developments are now progressing towards xe2x80x9csmartxe2x80x9d steering columns.
An object of the present invention is to provide a steering column which can be collapsed in the event of a vehicle crash in a way that takes into account various physical characteristics of the driver, such as weight, posture, position and dimensions.
According to the present invention, there is provided a collapsible steering column assembly including means to absorb energy transmitted by the steering column upon collapse, said means including a deformable element associated with a mounting means of the steering column, the mounting means including a mounting bracket slidably housing a skid member coupled to the steering column and adjoining deformable element, so that, upon collapse of the steering column, said skid member is urged in a direction to deform said deformable element which thereby absorbs collapse energy, said deformable element being in the form of a length of wire, with arms arranged to embrace, during steering column collapse, at least one extendable and retractable pin, said skid member acting to draw the clip over said at least one pin to deform the wire.
The or each pin can be solenoid operated, with the pins being normally retracted.
In the event of vehicle crash, the or each solenoid is fired so that the or each pin can be selectively used in accordance with a predetermined setting for energy absorption depending upon the data received from the driver sensors.
More than one deformable wire can be provided and the or each solenoid can select/de-select wires to increase/decrease the energy absorption capability. This arrangement can be used with a single wire arrangement or a multiple stack of wires, with the or each solenoid activating its pin to a predetermined depth.
A further development would be to use pairs of solenoid-operated pins utilising only one wire in each unit.